There have conventionally been proposed a variety of guidewires for guiding a catheter or the like, which is used by being inserted into tubular organs such as vessels, digestive tracts and ureters, and intracorporeal tissues, for the purpose of treatment or experiment. For example, there are one formed by doubly providing coils in a distal portion of a core shaft (for example, see Japanese Translation of PCT Publication Nos. 6-501179 and 2006-511304), one formed by using a stranded wire made up of a plurality of strands inside the coil of the distal portion (for example, see Japanese Patent Application Laid-Open No. 2008-161491), and the like.
Further, a guidewire for use in a relatively severe stenotic part of a vessel, typified by a part with stenosis named chronic total occlusion (CTO), needs to pass through a narrow lesion part. For this reason, as this guidewire, there is one having a tapered coil portion in a tip portion of a core shaft, and the tapered coil portion has a coil with a reduced outer diameter in the tip portion (for example, see Japanese Translation of PCT Publication No. 6-501179, FIG. 5, and Japanese Patent Application Laid-Open No. 2001-178829).